The main angle of car four wheel alignment:
Definition: The angle formed by the front centerline of the tire and the long vertical line of the lead from the front of the car is called the camber angle. It is stipulated that the wheel is inclined outwardly and the wheel is inclined inward to be negative.
Function: When the vehicle is fully loaded, the deformation of the suspension causes the wheel to tilt, avoiding the partial wear of the tire and reducing the load on the hub bearing. Reduce the distance between the grounding point of the longitudinal rotation of the front wheel and the extension line of the center pin centerline to the intersection of the ground, so that the steering is light.
King pin inclination
Definition: From the front of the car, the angle between the centerline of the steering shaft and the vertical line of the ground is called the kingpin inclination. It is stipulated that the kingpin is inclined inward and positive, and the kingpin is inclined outward to be negative.
Function: Make the steering light and make the positive torque also after the front wheel is turned.
King pin back angle
Definition: From the side of the car, the angle formed by the centerline of the steering shaft and the vertical line of the ground is called the caster angle. It is stipulated that the kingpin is inclined backwards and the kingpin is tilted forward to be negative.
Function: When the car is running, the steering wheel is occasionally deflected by external force and the steering pin will produce the torque of the wheel turning in the opposite direction to make the wheel automatically return to the positive direction of the car.
Front toe angle
Definition: Looking from the top of the car, the angle between the centerline of the tire and the longitudinal geometric centerline of the car is called the toe angle. It is stipulated that the distance between the front edges of the two wheels is less than the distance between the rear edges, and vice versa. The angle between the centerlines of the two tires is called the total toe.
Function: Eliminate the adverse consequences caused by wheel camber and reduce the pressure of the hub bearing and the wear of the tire.
Thrust angle: The bisector of the total toe angle of the rear wheel is called the thrust line. The angle between the geometric centerline of the body and the thrust line is called the thrust angle. The sign of the thrust angle specifies that when the thrust line is left-biased, the thrust angle is positive, and vice versa.
Steering front angle: The difference between the corners of the two front wheels when the wheel is turning is called the steering front angle. The measured value is usually measured with a steering angle of 20°.
Containment angle: From the front of the car, the angle between the kingpin axis and the centerline of the wheel tire is called the containment angle. It is numerically equal to the sum of the caster camber and the wheel camber.
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